1. Field of the Invention
The present invention relates to fuel tanks configured to suppress a liquid noise caused by a rapid movement of fuel when a vehicle accelerates or decelerates.
2. Description of the Background Art
In the field of vehicle fuel tanks, plastic fuel tanks formed by employing blow molding are known. Such plastic fuel tanks include features which are intended to suppress a liquid noise caused by a rapid movement of fuel when a vehicle accelerates or decelerates. Japanese Utility Model Laid-Open Publication Nos. HEI-2-34443 and SHO-57-32909, for example, propose fuel tanks provided with a barrier wall(s) (absorber) for checking movement of fuel in a tank during vehicle acceleration or deceleration.
First, a fuel tank disclosed in HEI-2-34443 will be described with reference to FIG. 14.
Referring to FIG. 14, a fuel tank 300 includes a tank body 301 for storing fuel, and a suppression wall 303 provided within the tank body 301 for suppressing a surge of fuel 302 when a vehicle accelerates or decelerates. The suppression wall 303 is formed with a plurality of through holes 304 to permit passage of the fuel 302. The suppression wall 303 is formed separately from the tank body 301, and is inserted when the tank body 301 is blow molded, and after the blow molding, is welded to the tank body 301.
The fuel tank 300, however, has the disadvantage that the suppression wall 303 formed separately from the tank body 301 results in an increased number of components and an increased number of manufacturing steps.
Next, a fuel tank disclosed in SHO-57-32909 will be described with reference to FIG. 15.
Referring to FIG. 15, a fuel tank 310 includes a tank body 311 for storing fuel, and a pair of hollow wave cancellation boards 313, 313 provided integrally within the tank 311 and spaced longitudinally for suppressing movement of fuel 312. The wave cancellation boards 313 each have wave cancellation pieces 314, 315 integrally formed within the tank body 311 from above and below when the tank body 311 is blow molded. They are configured to prevent surging of the fuel 312 when a vehicle accelerates or decelerates (hereinafter, referred to as a “liquid movement suppression effect”).
However, the fuel tank 310 has the problem that use of the wave cancellation boards 313, 313, having a given volume and provided in two places within the tank body 311, leads to a reduced volume of the tank body 311 and a reduced capacity of storing the fuel 312.
Therefore, there is demand for fuel tanks having a liquid movement suppression effect, without increasing the number of components, and which minimizes both the number of manufacturing steps and a reduction in the fuel storage capacity.